摘要：前言我一生的文章都會放在這里，我的博客，我希望每一行代碼，每一段文字都能幫助你。大家好，我是，今天我們不聊工具規(guī)范等等等等的輔助，就聊一下該如何寫一段好的代碼，本文以我的職業(yè)生涯碰到的代碼為例，如有出入請在評論區(qū)提出異議，謝謝。

我一生的文章都會放在這里，我的博客，我希望每一行代碼，每一段文字都能幫助你。https://github.com/CrazyCodes...

大家好，我是CrazyCodes ，今天我們不聊工具、規(guī)范等等等等的輔助，就聊一下該如何寫一段“好”的代碼，本文以我的職業(yè)生涯碰到的代碼為例，如有出入請在評論區(qū)提出異議，謝謝。

搜索很常見，復雜的搜索大多出行在后臺，舉個栗子，大概需求是這樣的

這是一個后臺用戶列表的搜索功能

看到這些例子你是否不由的一顫，又要開始造輪子的是不是？
以原生的例子為例，開始你可能會這樣寫(以下為偽代碼)

if (IS_POST) {
    $like = "";
    if (isset($_POST["username"])) {
        $username = $_POST["username"];
        $like .= "username like "%" . $username . "%" and ";
    }

    if (isset($_POST["phone"])) {
        $phone = $_POST["phone"];
        $like .= "phone like "%" . $phone . "%" and";

    }

    if ($_POST["is_auth"]) {
        $isAuth = $_POST["is_auth"];
        $like .= "is_auth like "%" . $isAuth . "%" and";

    }

    if ($_POST["sex"]) {
        $sex = $_POST["sex"];
        $like .= "sex like "%" . $sex . "%" and";
    }


    if ($_POST["time"]) {
        $time = $_POST["time"];
        $like .= "time like "%" . $time . "%" and";
    }


    if ($_POST["wallet"]) {
        $wallet = $_POST["wallet"];
        $like .= "wallet like "%" . $wallet . "%" and";

    }

    $like = rtrim($like, "and");

    $sql = "SELECT * FROM `user` WHERE {$like}";


} else {
    return view("user");
}

恩...,還不錯，結(jié)構(gòu)清晰，傳統(tǒng)的初學者條型代碼，接下來我們先封裝一下幾塊代碼。

function post($param)
{
    return isset($_POST[$param]) ? $_POST[$param] : null;
}

if (IS_POST) {
    $like = "";
    if (post("username")) {
        $username = post("username");
        $like .= "username like "%" . $username . "%" and ";
    }

    if (post("phone")) {
        $phone = post("phone");
        $like .= "phone like "%" . $phone . "%" and";

    }

    if (post("is_auth")) {
        $isAuth = post("is_auth");
        $like .= "is_auth like "%" . $isAuth . "%" and";

    }

    if (post("sex")) {
        $sex = post("sex");
        $like .= "sex like "%" . $sex . "%" and";
    }


    if (post("time")) {
        $time = post("time");
        $like .= "time like "%" . $time . "%" and";
    }


    if (post("wallet")) {
        $wallet = post("wallet");
        $like .= "wallet like "%" . $wallet . "%" and";

    }

    $like = rtrim($like, "and");

    $sql = "SELECT * FROM `user` WHERE {$like}";


} else {
    return view("user");
}

恩，至少我們可以自由控制post方法了，但是這類過程化代碼維護性太低，我們再改進下

function post($param)
{
    return isset($_POST[$param]) ? $_POST[$param] : false;
}

function postAll()
{
    return $_POST;
}

if (IS_POST) {
    $like = "";


    foreach (postAll() as $key => $value) {
        if (post($key)) {
            $like .= "{$key} like "%{$value}%" and";
        }
    }

    $like = rtrim($like, "and");

    $sql = "SELECT * FROM `user` WHERE {$like}";


} else {
    return view("user");
}

function request($param = null)
{
    return new Request($param);
}

class Request
{
    public function __construct(string $param = null)
    {
        return isset($_POST[$param]) ? $_POST[$param] : false;
    }

    public function all()
    {
        return $_POST;
    }
}


class User
{
    public function index()
    {
        if (IS_POST) {
            $like = "";

            foreach (request()->all() as $key => $value) {
                if (request($key)) {
                    $like .= "{$key} like "%{$value}%" and";
                }
            }

            $like = rtrim($like, "and");

            $sql = "SELECT * FROM `user` WHERE {$like}";

        } else {
            return view("user");
        }
    }
}

function request($param = null)
{
    return new Request($param);
}

class Request
{
    public function __construct(string $param = null)
    {
        return isset($_POST[$param]) ? $_POST[$param] : false;
    }

    public function all()
    {
        return $_POST;
    }
}


class User
{
    public $request = [
        "username",
        "phone",
        "is_auth",
        "sex",
        "time",
        "wallet"
    ];

    public function index()
    {
        if (IS_POST) {
            $like = "";

            foreach (request()->all() as $key => $value) {
                if (in_array($key, $this->request) && request($key)) {
                    $like .= sprintf("%s like %s and", $key, $value);
                }
            }

            $like = rtrim($like, "and");

            $sql = "SELECT * FROM `user` WHERE {$like}";

        } else {
            return view("user");
        }
    }
}